One of the key challenges that Louis van Gaal faces in his new post as Manchester United manager is the rebuilding of the once-great Red Devils defence.
The departure of Rio Ferdinand and Nemanja Vidic—both past their prime but still decent—is a huge blow for the Old Trafford outfit, as they have represented part of the team's core for many years now and through many great successes.
The players Sir Alex Ferguson brought in to potentially replace the duo—Phil Jones, Chris Smalling, Jonny Evans—do not necessarily look up to the job, and thus at least one new centre-back is essential if United are to return to their former glories.
Long-rumoured target Mats Hummels would have been the perfect signing in the position, but his Borussia Dortmund manager Jurgen Klopp seems to have categorically ruled out the move, per Marc Williams in the Independent: "You know it's garbage. Hummels will stay at Dortmund."
Thus Van Gaal must look elsewhere in order to shore up a creaky central defence which looked lost at times last season, conceding 43 goals as the Red Devils finished seventh in the Premier League under David Moyes.
United need a return to the years in which they conceded fewer than 30 goals in a Premier League season—a constant between the 2006/07 and 2009/10 seasons when Vidic and Ferdinand were in their prime per ESPN FC.
As with during those terms they have an excellent goalkeeper—David de Gea was one of few positives last season—but Van Gaal now needs to find his own defensive duo.
But who are his potential options? Stefan de Vrij looks to be on the market and eager to make a move to work with his former Netherlands boss, per Dutch football writer Elko Born:
The 22-year-old Feyenoord player has excelled in the Eredivisie, per Opta, and his familiarity with Van Gaal's methods would surely be a big plus:
Furthermore, he performed admirably at the World Cup in Brazil as the Netherlands came third, proving that he has the ability to perform at the top level as well as in the Dutch league, per WhoScored.com's Ben McAleer:
A youngster who is only going to improve, he looks to be good value at Feyenoord's asking price and could slip straight into the United back line.
Football journalist Tom McDermott also reports the interest and suggests that Vermaelen's versatility—he can play centrally and on the left—and decent price tag—reportedly £10 million per Cross—make the 28-year-old a good target:
Indeed, his familiarity with the Premier League also makes him a potentially strong signing for United as he has proven his quality in the English top flight and could certainly perform well in the Red Devils defence.
New attacking players are certainly needed at United, but the centre of defence is a key area in which they need to strengthen and should be a priority.
Fewer goals conceded will automatically improve results as United look to return to the summit of the English top flight, and Van Gaal needs to make the signings soon so that his new defence can work together before the start of the new season.